refactor(db): Rewrite database code to use sqlx instead of rusqlite (#…

…1340)

* sqlx initialization

* Finish initial pass of refactor

* Finish refactor, document how to use sqlx

* Remove rusqlite dependency

* Fix most tests

* [autofix.ci] apply automated fixes

* All tests pass

* [autofix.ci] apply automated fixes

* Update docs

* Fix conflicts

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Co-authored-by: autofix-ci[bot] <114827586+autofix-ci[bot]@users.noreply.github.com>

.env

@@ -0,0 +1 @@
+DATABASE_URL=sqlite://ee/tabby-db/schema.sqlite